To improve sound quality, many speakers adopt a 2-way system in which sound waves in a low-pitched sound range are emitted from a woofer and sound waves in a high-pitched sound range are emitted from a tweeter. In a common 2-way speaker system, the tweeter and the woofer are arranged in a vertical direction or a horizontal direction. Therefore, the common 2-way speaker system needs to have a wider area on a front surface (baffle plate) thereof than a single-cone speaker having one cone.
Here, proposed is a speaker system in which the tweeter and the woofer are arranged in a front-back direction. In many of such speaker systems, the tweeter and the woofer are coaxially arranged, and such speaker system is called “coaxial speaker” (see Patent Document 1 for example). In a common coaxial speaker, the tweeter is smaller than the woofer, and is arranged in front of the woofer or inside a cone of the woofer. Therefore, the area of the front surface of the speaker system can be reduced, so that the speaker system can be reduced in size.
Patent Document 1: Japanese Laid-Open Patent Application Publication 2004-165917